You don't mention how long you've been on the entocort or if you're tapering.
C-reactive protein is a marker for inflammation, but it is not necessarily specific to Crohn's inflammation. If you were fighting off a cold, for example, your C-RP could elevate. Maybe even the endometriosis could affect it. It may be that the difference between 12 and 16 is not significant enough for your GI to be concerned. If you are having D with blood and mucus--and that's a new development--that may change things, you should talk to your GI again. But a day or two of minimal blood is possible after a colonsocopy with biopsies.
You already have a doctor set up for your trip... Try to relax and enjoy it. Maybe plan get labs done halfway through if you are concerned you might be worsening. But stress will aggravate the IBS and possibly the IBD as well, so focus on having fun but maybe be careful what you eat.
July 2007 Drug-Induced Liver Injury
January 2008 Crohn's Ileitis
Enteral Nutrition, Omega-3 (Flax Oil and Fish Oil), VSL#3, Vitamin E, Folic Acid, Psyllium